I've got a small truck-sub-box and an amp that I want to put in the back of the wagon, quick release style. My question is does the standard FM/CD deck in the 05's have pre-out's? How does the factory sub hook up, and is that only available with the optional 6disk? I'm not looking for huge sound, just a bit more with what I have without spending too much money.

 

No, the factory HU does not have pre-outs, most OEM HU's don't. The factory sub connects with an adapter harness that bridges the signal from the rear speaker outputs.
The only way to connect external aftermarket amps or subs to the OE HU is to either use a line-output converter that converts the speaker-level outs to preamp level, or to use equipment that accepts speaker-level inputs. Although these methods do work, you would really be better off replacing the HU with a good aftermarket one that has preamp outs. The result will be far better sound quality and additional features as well, such as MP3 and XM/Sirius options.

 

I had an amp with speaker level inputs running my sub at first, to hold me over until I got the scratch for a new HU. It's definitely doable and it sounds pretty good. I used vampire taps behind the factory stereo.

 

Thanks for the info, that’s about what I was expecting. Forgive my stereo Noob-ness but what is the difference in pre-amp and speaker level outputs? I’ve been looking around at new decks. But I can’t help but think that the ones with nicer features look like a marquee sign on the Vegas strip. Any suggestions on good quality deck with MP3/Sat. that doesn’t have unnecessary junk built in.

 

Pre-amp (line level) signals are not amplified, they are meant to input into other audio equipment. They also aren't affected by the volume adjuster.

Speaker level signals are amplified and are intended to go to speakers.

As far as HU recommendations, I bought a cheap deck but I like it: http://www.cardomain.com/item/PIODEHP4600MP

 

That looks like a nice unit, I'll keep it in mind..